1. Field of the Invention
This invention relates to large elongate liquid holding vessels in which liquids and activities in and on the liquids can be contained and controlled.
More specifically, this invention relates to liquid holding vessels of the type described above wherein the vessels are formed of materials that can readily be assembled to form an elongate raceway.
Still more specifically, this invention relates to vessels as described above wherein the elongate portion of the raceway may be rolled for transport and laid flat for cleaning and repair.
Still more specifically, this invention relates to vessels as described above wherein the vessels will maintain their shape without additional supports when filled with flowable material and supported by liquids or by solids or by granular material.
2. Description of the Related Art
The art of constructing large elongate vessels for holding flowable materials has become of interest for diverse applications. Elongate raceways constructed for the purpose of controlling the flowable materials and their environs as well as controlling activities in and on the flowable materials has become of great interest to a number of industries. Such vessels find applications in food processing such as the making of cheese and wine, the practice of swimming and rowing, testing of marine engines and craft, and in waste management.
There has long been a need for a low cost large long vessel that is transportable and which is self supporting in land and water
The following disclosures will address the raceway of this invention, as it would be employed in aquaculture, but the scope of the invention should be understood to encompass applications that would be made readily apparent to one skilled in the art by the disclosures of this invention.
In aquaculture a raceway is defined as an elongate horizontal channel through which water flows from a head end to a tail end.
In aquaculture such raceways are employed to rear high densities of marine life having commercial value. Fish, shrimp, and crayfish are often raised commercially and to a lesser degree many other forms of aquatic life and plants have been successfully grown by means of aquaculture.
Aquaculture is practiced in natural and man made ponds as well as in tanks or raceways placed in ponds or established on land and even in buildings. The use of raceways enables the raising of dense populations of aquatic life and provides the capacity for a grower to control the quality of the water entering the head end of the raceway and the flow rate of the water leaving the tail end of the raceway and to have some control over the raceway's environment.
Heretofore, raceways of the type described above have exhibited a number of deficiencies that have negative effects on successful aquaculture. The extensive use of prior art raceways in profitable aquaculture is inhibited by their cost and lack of durability.
Efficient aquaculture requires the use of optimal densities of the aquatic life that is being cultured in the raceways. In such dense monocultures the immune distance for most diseases that harm the culture is not maintained. It is therefore critical to control the entry of diseases or toxins into the raceway and to be able to isolate any population that does become diseased. Further, if an infection or disease does enter a raceway, prior art raceways are difficult or impossible to remove from service and clean and sanitize and return to service.
It is an object of this invention to provide an aquaculture vessel that is portable, low in cost, and durable.
It is further an object of this invention to provide the vessel as described above that can readily be removed from service and cleaned and repaired as needed.
It is further an object of this invention to provide a vessel as described above that can be combined in an array of such vessels to serve the user's needs.
It is further an object of this invention to provide a vessel as described above wherein the vessel is equally adaptable to water or land supported applications.
Other objects will be made apparent from the following specifications, drawings and claims.
The prior art abounds in large vessels formed of open mesh materials for use in aquaculture on or in lakes streams and ponds. Such systems permit water born agents from the surrounding pond to enter the vessel. These agents can be harmful to the aquaculture or become an encumbrance to the vessel. Such open mesh vessels also limit the ability of the user to control the condition of and flow of water into and out of the vessel.
To overcome these defects in open mesh systems, the art has developed large elongate closed vessels called raceways. An aquaculture raceway can be defined as an elongate trough into which water flows at a head end and from which water exits at a tail end. Such troughs permit the control of the condition of the water entering and leaving the raceway and permit the culturing of dense populations of aquatic life.
U.S. Pat. No. 4,044,059 to Long teaches a raceway for culturing fish wherein the raceway is formed of a relatively thin flexible pool liner material stretched over a rigid frame and supported on a body of water by a floatation means or docks wherein a multiplicity of raceways may be interconnected to enable the sharing of water pumping, conditioning and cleaning means. Frames and liners such as taught by Long are expensive, and require significant maintenance. They also are limited to support on a body of water and are not readily transportable,
U.S. Pat. No. 4,044,720 to Fast also teaches the use of a relatively thin pond liner and rigid u-shaped raceway frame supported on a pond by means of a dock or floatation means and which can be interconnected with similar raceways to share related equipment and operations. The u-shaped cross-section permits more uniform flow of water through the raceway and facilitates cleaning and maintenance. The raceways of Fast are relatively expensive and need continual maintenance and repair and are not readily rendered portable.
U.S. Pat. No. 4,688,519 to Fisher teaches a land based system of raceway like tanks made of concrete or wood having fiberglass or epoxy liners attached wherein the tanks have a cylindrically curved concave bottom portion which permits the use of a centrally pivoted bottom following member which serves to resuspend food and to introduce aerated water. Such land based systems are not readily adapted to water based use and are not readily rendered portable. They are also relatively expensive to construct and maintain.